oop/lab/lab9/Question6/Car.java

/*
 * Author: CHEN Yongyuan (Walter) 1930006025 from OOP(1007)
 * Date: 2022-04-21
 * Description: This is the class of Door.
 */

public class Car {
	private String name;
	private Door[] doors;

	/**
	 * Constructor.
	 *
	 * @param name          The name of the car.
	 * @param numberOfDoors The number of doors.
	 * @throws BadCarException If the number of doors is less than 1.
	 */
	public Car(String name, int numberOfDoors) throws BadCarException {
		if (numberOfDoors < 1) {
			throw new BadCarException("A car must have at least one door!");
		}

		this.name = name;

		// initialise the doors array
		doors = new Door[numberOfDoors];
		for (int i = 0; i < numberOfDoors; i++) {
			doors[i] = new Door();
		}
	}

	/**
	 * Prints each door of the car.
	 */
	public void listDoors() {
		for (Door door : doors) {
			System.out.println(String.format("%s: door is %s", name, door.isOpen() ? "open" : "closed"));
		}
	}

	/**
	 * Count the numer of open doors.
	 *
	 * @return The number of open doors.
	 */
	public int countOpenDoors() {
		int count = 0;
		for (Door door : doors) {
			if (door.isOpen()) {
				count++;
			}
		}
		return count;
	}

	/**
	 * Open one door with number start from 1.
	 *
	 * @param doorNumber The number of the door to open start from 1.
	 * @throws BadDoorException If try to open a non-existed door.
	 */
	public void openOneDoor(int doorNumber) throws BadDoorException {
		doorNumber--;
		if (doorNumber < 0 || doorNumber >= doors.length || doors[doorNumber] == null) {
			throw new BadDoorException(String.format("Door %d does not exist!", doorNumber + 1));
		}

		doors[doorNumber].open();
	}

	/**
	 * Open all the closed doors and closes all the open doors.
	 */
	public void changeAllDoors() {
		for (Door door : doors) {
			if (door.isOpen()) {
				door.close();
			} else {
				door.open();
			}
		}
	}

	/**
	 * Replaces the existing car door with a completely new door.
	 *
	 * @param doorNumber The number of the door to replace start from 1.
	 * @throws BadDoorException if replace a non-existed door.
	 */
	public void replaceDoor(int doorNumber) throws BadDoorException {
		doorNumber--;
		if (doorNumber < 0 || doorNumber >= doors.length || doors[doorNumber] == null) {
			throw new BadDoorException(String.format("Door %d does not exist!", doorNumber + 1));
		}

		// replace the door.
		doors[doorNumber] = new Door();
	}

	/**
	 * Replace all doors.
	 */
	public void replaceAllDoors() {
		for (int i = 0; i < doors.length; i++) {
			doors[i] = new Door();
		}
	}

	/**
	 * Replace existing doors start from the first door with the number of doors.
	 *
	 * @param numOfDoorsToReplace The number of doors to replace.
	 */
	public void replaceManyDoors(int numOfDoorsToReplace) {
		for (int i = 0; i < numOfDoorsToReplace; i++) {
			doors[i] = new Door();
		}
	}

	/**
	 * Adds two new doors to the car.
	 */
	public void expandCar() {
		Door[] newDoors = new Door[doors.length + 2];

		// copy the old doors to the new array.
		for (int i = 0; i < doors.length; i++) {
			newDoors[i] = doors[i];
		}

		// initialise the new doors.
		for (int i = doors.length; i < newDoors.length; i++) {
			newDoors[i] = new Door();
		}

		doors = newDoors;
	}

	/**
	 * Test.
	 */
	public static void testCar() {
		try {
			Car brokencar = new Car("Broken", 0);
		} catch (BadCarException ex) {
			System.out.println(ex.getMessage() == "A car must have at least one door!");
		}
		Car c = null;
		try {
			c = new Car("Biggy", 7);
		} catch (BadCarException ex) {
			System.out.println("BUG! This must never happen!");
		}
		c.listDoors();
		System.out.println(c.countOpenDoors() == 0);
		c.changeAllDoors();
		System.out.println(c.countOpenDoors() == 7);
		c.listDoors();
		c.changeAllDoors();
		System.out.println(c.countOpenDoors() == 0);
		try {
			c.openOneDoor(8);
		} catch (BadDoorException ex) {
			System.out.println(ex.getMessage().equals("Door 8 does not exist!"));
		}
		try {
			c.openOneDoor(3);
		} catch (BadDoorException ex) {
			System.out.println("BUG! This must never happen!");
		}
		System.out.println(c.countOpenDoors() == 1);

		c.changeAllDoors();
		System.out.println(c.countOpenDoors() == 6);
		c.listDoors();
		c.changeAllDoors();
		System.out.println(c.countOpenDoors() == 1);
		c.listDoors();
		try {
			c.replaceDoor(8);
		} catch (BadDoorException ex) {

			System.out.println(ex.getMessage().equals("Door 8 does not exist!"));
		}

		try {
			c.replaceDoor(3);
		} catch (BadDoorException ex) {
			System.out.println("BUG! This must never happen!");
		}
		System.out.println(c.countOpenDoors() == 0);

		c.listDoors();
		c.changeAllDoors();
		System.out.println(c.countOpenDoors() == 7);
		c.listDoors();
		c.replaceAllDoors();
		System.out.println(c.countOpenDoors() == 0);
		c.listDoors();
		c.changeAllDoors();
		System.out.println(c.countOpenDoors() == 7);
		c.listDoors();
		c.replaceManyDoors(4);
		System.out.println(c.countOpenDoors() == 3);
		c.listDoors();
		try {
			c.replaceManyDoors(20);
		} catch (ArrayIndexOutOfBoundsException ex) {
			System.out.println(ex.getMessage().equals("Index 7 out of bounds for length 7"));
		}

		System.out.println(c.countOpenDoors() == 0);
		c.listDoors();

		c.expandCar();
		c.changeAllDoors();
		System.out.println(c.countOpenDoors() == 9);
		c.listDoors();
	}
}